This is not very obvious. It may occur due to some problem in the server or due to a bug in the website. Now for the SSC CPO examination, the age must be less than 28 year of age before 1st January,2022. As a result, if you won't be able to apply for the examination, then I would suggest you to contact the SSC Regional Network.

For more information regarding SSC CPO consider the link provided below:

https://competition.careers360.com/articles/ssc-cpo-eligibility-criteria

For more information regarding Regional Network in SSC, consider the link below:

https://ssc.nic.in/Portal/RegionalNetwork

I hope this helps. Wish you a great day!